MoTeC Global Forum

I would like to know if the 1.5 MS rule can be changed to something less. I have ordered a set of billet atomizer injectors 160 lb injectors and they can be operated safely to 1.2 ms in closed loop. I am presently considering purchasing a motec ecu but I am concerned about not having closed loop idle.

http://www.billetatomizer.com/

very interesting product. although i couldn't imagine .3 of a ms should be a deciding factor on a 1000hp+ car that requires 100+lb/hr injectors.

not sure what type of vehicle your putting it in or engine size etc... but at idle a 1000hp engine is still going to require a fair bit of fuel. I can't comment on all applications but I don't think i've run into too many big hp engines that are very much under 2.0ms at idle, maybe 1.8 at the lowest i can recall.

possibly some others can chime in with their tuning experience for this

Its a turbocharged 3.8 litre motor, it requires very little fuel at idle.I would just like to have the option of being to change the 1.5ms rule, for spending so much on a ecu, you should get what you want correct?

Do you really need closed loop idle though ?

You should be able to tune open loop for a very good stable idle with quite sensible AFR's

I worked on a 4cyl car with ID2000's and it quite happily runs in the 14.x range AFR's on open loop, M800.

Stevie, I understand what your saying, but I have things like the AC compressor kicking in, cooling fans, I could see big fluctations in open loop. I'm not saying it could be the best situation, but I would just not like to be forced to use open loop, each combo is different. ALso I am looking at traction control option and I think it does not cut boost, is this correct?

norm wrote:Stevie, I understand what your saying, but I have things like the AC compressor kicking in, cooling fans, I could see big fluctations in open loop. I'm not saying it could be the best situation, but I would just not like to be forced to use open loop, each combo is different. ALso I am looking at traction control option and I think it does not cut boost, is this correct?

If battery compensatons and idle control are set properly, A/C or cooling fans shouldnt interfere that much.

As for traction control

Any Ive seen, and Ive never used Motecs...they usually retard timing first, or complete spark cut in order to reduce power.
Some standalone traction control systems will kill the injectors on alternate cylinders in order to reduce power.

Using boost control would be very slow to respond by comparison.